Have you seen Australian Tree Fern (Cyathea cooperi)?
Hawaii Early Detection Network Priority Pest for the islands of Maui, Lanai, Molokai, and the Big Island Hawaii


Rubber vine flower detail
Australian tree ferns can jump the fence into the forest, as seen here on the road to Hana, Maui
Rubber vine detail
White scales at base of the fern fronds
Rubber vine
Mature leaves form tight rosette at top of trunk
Images: Forest & Kim Starr

Identification: Australian tree fern is widespread in Hawaii, but is currently only known to grow in a few locations on Molokai and Lanai (see map.) This tree fern grows up to 12 m (40 ft) tall or more. Stem is covered by a cleancut OVAL SCAR PATTERN. Long WHITE and short RED-BROWN SCALES found at the base of the fronds (see this identification aid for more help). Leaves of mature plants grouped in a TIGHT ROSETTE at top of stem, rather than spread out along the stem. Sori (clusters of spores) on middle of the pinnae, or fern leaflet divisions. Found in residential areas escaping into wild areas.
Impacts: This fast growing fern, which is well-suted to shade, has wind spread spores can travel over 12 km (7 miles) from parent plant, which allows plants to be transported from the garden directly into the rainforest. Once established in the rainforest it diplaces other understory vegetation.
Dispersal Mechanism: The Australian tree fern is a common garden plant throughout Hawaii. Ferns reproduce via wind-borne spores. If you see it anywhere else on Maui, Molokai, Lanai, or the Big Island- let someone know!

More information about this pest external link


Australian Tree Fern look-alikes:


Cibotium chamissoi

Hapu'u (Cibotium species)

Hapu'u (Cibotium chamissoi):
The native Hawaiian tree fern, Hapu'u, has BLOND to RED COLORED HAIRS along the base of the trunk and POWDERY WHITE SORI (clusters of spores) on the EDGE of the pinnae. Hapu'u is a desireable garden alternative to Australian tree fern. Be aware, though, that the trunks of hapu'u often contain a variety of invasive alien plants, like Himalayan raspberry, growing on them and these could be a source of inadvertent introduction of noxious weeds onto your island. Examine all hapu'u used and remove clinging vegetation.

Hapuu

Detail of red hairs at
base of Hapu'u fronds

Last Updated: . If you have any questions about the Hawaii Early Detection Network contact reportapest-maui@lists.hawaii.edu.